Finding the Exact Value of sin[2arcsin(3/5)] with Inverse Trig Functions

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Homework Statement


Find the exact value of the expression:


Homework Equations


sin[2arcsin(3/5)]


The Attempt at a Solution


I know you're supposed to use sin2x=2sinxcosx somehow but not sure how to start.
 
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page13 said:

Homework Statement


Find the exact value of the expression:


Homework Equations


sin[2arcsin(3/5)]


The Attempt at a Solution


I know you're supposed to use sin2x=2sinxcosx somehow but not sure how to start.

Start by letting u = arcsin(3/5). Then your expression is sin(2u) = ?

It will be helpful to draw a right triangle where u is one of the acute angles. Label the sides and hypotenuse so that sin(u) = 3/5.
 
Ah, OK! 24/25 correct?